LG 3

Female Reproductive System Study Notes

Objectives

  • By the end of studying this topic, the student should be able to:
    • List the main external and internal female reproductive organs.
    • Describe the location, coverings, and blood supply of the ovary.
    • Explain the parts of the uterine tube and uterus.
    • List the structures that support the uterus.
    • Describe the surface anatomy and lymphatic drainage of the breast.
    • Discuss clinical correlations related to the female reproductive system.

Clinical Scenarios

  • Case 1: A 25-year-old pregnant woman at 30 weeks of gestation presents with pelvic pain due to the enlarging uterus exerting pressure on surrounding pelvic structures.

    • Question: Which structure is most likely to be displaced anteriorly by the expanding uterus?
    • Options:
      A) Rectum
      B) Bladder
      C) Ureter
      D) Vagina
      E) Sacral plexus

  • Case 2: A 37-year-old woman with pelvic pain and ascites undergoes drainage through the anterior uterus.

    • Question: Into which space must the needle pass to remove the fluid?
    • Options:
      a. Rectouterine pouch
      b. Pararectal fossa
      c. Paravesical space
      d. Uterovesical pouch
      e. Superficial perineal pouch

  • Case 3: A 42-year-old woman admitted to the emergency department with severe abdominal pain has a tumor at her left ovary. A frozen biopsy reveals ovarian carcinoma.

    • Question: Which actions can be performed to reduce the pain from the ovarian carcinoma?
    • Options:
      a) Cut the suspensory ligament.
      b) Cut the utero-ovarian ligament.
      c) Cut the ovarian ligament.
      d) Cut the round ligament.
      e) Cut the broad ligament.

Overview of Female Reproductive System

  • The female reproductive system consists of:
    • External genital organs (Vulva):
    • Labia Majora
    • Labia Minora
    • Vestibule of the vagina
    • Clitoris
    • Internal genital organs:
    • Ovaries
    • Uterine tubes (fallopian tubes)
    • Uterus
    • Vagina

Bony Pelvis

  • Structure of the pelvis includes:
    • Pelvic cavity
    • Pelvic floor
    • Perineum

Ovaries

  • Location:

    • Upper pelvic cavity, on either side of the uterus (ovarian fossa).

  • Position Maintenance:

    • Maintained by ligaments:
    • Suspensory ligament
    • Ovarian ligament
    • Broad ligament

  • Structure:

    • Contains a large number of primary follicles.

  • Functions:

    • Produce ovum, estrogen, and progesterone.

  • Boundaries of the ovarian fossa:

    • Anteriorly: external iliac vein and artery
    • Posteriorly: ureter and internal iliac vessels
    • Inferiorly: superior vesical artery
Extremities (Poles) of the Ovary

  • Superior Extremity:

    • Broader; related to uterine tube and external iliac vein.
    • Provides attachment to suspensory ligament of the ovary (contains ovarian vessels and nerves).

  • Inferior Extremity (Pole):

    • Narrower; related to pelvic diaphragm.
    • Connected to the lateral uterus by the ligament of the ovary.
Blood Supply and Nerve Supply of the Ovaries
  • Arteries:
    • Uterine artery (internal iliac artery)
    • Ovarian artery (abdominal aorta)
  • Veins:
    • Right side drains into inferior vena cava
    • Left side drains into left renal vein
  • Lymph Drainage:
    • Internal iliac and para-aortic nodes.
  • Nerve Supply:
    • Sympathetic and parasympathetic nerves from the inferior hypogastric plexuses.
Clinical Correlations of the Ovaries

  • Ovarian Torsion:

    • Occurs due to an abnormally long mesovarium and suspensory ligament of the ovary.

  • Prolapse of Ovaries:

    • Ovaries may be displaced into the pouch of Douglas; can be palpated through per vaginal examination.

  • Ectopic Ovaries:

    • May fail to descend into the pelvis or can be drawn downward with the round ligament of the uterus into the inguinal canal or labium majus.

Uterine Tubes (Fallopian Tubes)

  • Function:

    • Extend from the uterus to the ovaries; connect the uterine cavity to the peritoneal cavity.

  • Regions:

    • Subdivided into four parts:
    1. Uterine part (intramural part)
    2. Isthmus
    3. Ampulla (longest and widest part)
    4. Infundibulum (funnel-shaped termination with fimbriae)
Infundibulum

  • Description:

    • Funnel-shaped lateral end; opens into the peritoneal cavity near the ovary via abdominal ostium.
    • Direct communication between the female genital tract and peritoneal cavity allows the spread of pelvic inflammatory disease, leading to peritonitis.
    • Fimbriae function:
    • Capture ovum during ovulation and direct it into the tube.

  • Clinical Implication:

    • Ovum may implant in infundibulum leading to ectopic pregnancy.
Ampulla

  • Description:

    • Longest part (about 2/3 of the tube); common site for fertilization and ectopic pregnancy (70-80% of cases).

  • Complications:

    • If an embryo implants here, it cannot develop normally leading to rupture and life-threatening hemorrhage.
    • Blockage due to infection or scarring can lead to infertility.
Isthmus

  • Description:

    • Narrow, thick-walled segment.

  • Function:

    • Often used in tubal ligation procedures.
    • Post-inflammatory scarring can cause tubal blockage, resulting in infertility or ectopic pregnancy.
Intramural (Uterine) Part

  • Description:

    • Short segment passing through the uterus (myometrium) and opens into the uterine cavity at the uterine ostium.

  • Significance:

    • Narrowest portion of the uterine tube allowing passage of fertilized ovum into the uterine cavity.
Blood Supply of Uterine Tubes
  • Supplied by:
    • Ovarian and uterine arteries.
    • Corresponding veins drain into ovarian and uterine veins.
    • Lymph vessels follow veins draining into internal iliac, pre-aortic, and para-aortic lymph nodes.
Salpingitis
  • Definition:
    • Inflammation of uterine tubes caused by bacterial infection leading to potential adhesions that can block the lumen causing infertility or ectopic pregnancy.
Ectopic Pregnancy
  • If the lumen is partially occluded, sperm may fertilize the ovum, but the resulting egg may not pass into the uterus and may implant in the uterine tube.
Ligation of Uterine Tubes
  • Surgical method of sterilization preventing oocyte from passing into the uterus, thus preventing pregnancy.

Uterus

  • Function:

    • Organ of gestation where the fertilized oocyte becomes embedded and the organism develops until birth.

  • Location:

    • Within true pelvis, between urinary bladder and rectum.

  • Normal Position:

    • Anteverted: tilted forward between vagina and cervix.
    • Anteflexed: bent forward between body and cervix.
    • Retroversion: tilted backward potentially causes infertility, dysmenorrhea or back pain.
Anatomy of Uterus

  1. Fundus:

    • Rounded upper part above openings of uterine tubes; used to measure uterine height during pregnancy for fetal growth assessment.

  2. Body (Corpus):

    • Contains uterine cavity, triangular in shape,
    • Anterior (vesical surface) - Between uterus and bladder
    • Posterior (intestinal surface) - Between uterus and rectum.

  3. Cervix:

    • Constricted part located between body and cervix, corresponds to internal os.
    • External os opens into the vagina; it has:
      • Internal os: junction with the uterine body.
      • Cervical canal: cavity between internal and external os.
    • Site for cesarean section incision; pelvic splanchnic nerves (S2–S4) transmit pain from cervix and lower uterus leading to deep pelvic pain during menstruation.
Blood Supply to the Uterus
  • Main Arterial Supply:
    • Uterine artery from internal iliac artery; anastomoses with ovarian and vaginal arteries.
  • Ureter Relationship:
    • Uterine artery crosses ureter approximately 2 cm lateral to cervix; close anatomical relationship raises risk of injury during hysterectomy.
    • Mnemonic: “Water under the bridge” - the ureter (water) passes under the uterine artery (bridge).
  • Venous Drainage:
    • Uterine plexus drains into internal iliac vein.
Supports of the Uterus

  • Main Support Mechanism:

    • Tone of levator ani muscles and condensations of pelvic fascia which form the following ligaments:

    • A. Levatores Ani Muscles and Perineal Body:

      • Important in maintaining pelvic floor integrity; damage during childbirth can lead to prolapse of pelvic viscera.

    • B. Pelvic Fascia:

      1. Transverse Cervical (Cardinal) Ligaments:
      • Pass from vagina to laterally wall of pelvis; provide direct support to uterus.
      1. Pubocervical Ligaments:
      • Pass from cervix to bladder neck.
      1. Sacrocervical Ligaments:
      • Extend to cervix and upper end of vagina from sacrum.

    • C. Peritoneal Folds:

      • Broad Ligaments of the Uterus: Drapelike folds of peritoneum related to uterine tubes and artery.
      • Round Ligaments of the Uterus: Extend from superolateral angle of uterus through inguinal canal to subcutaneous tissue of labium majus.
Clinical Note on Ligaments
  • Broad and Round Ligaments:
    • Lax structures allowing movement of uterus; assist in maintaining it anteverted and anteflexed, but stretch during pregnancy.
Parts of the Broad Ligament
  • Components include:
    • Mesosalpinx:
    • Infundibulo-pelvic ligament:
    • Mesometrium:
    • Mesovarium:
  • Structural relationships of these parts include:
    • Ovary, uterus, and associated structures.

Vagina

  • Description:
    • Muscular tube about 10 cm long, extends from cervix to vaginal orifice.
    • Located between bladder (anterior) and rectum (posterior).
    • Lined with folds (rugae) allowing stretch during childbirth.
Main Functions of the Vagina
  1. Allow discharge of menstrual flow.
  2. Serve as female organ of coitus.
  3. Allow passage of fetus from the uterus during childbirth.
Fornices
  • Approximately 7-9 cm long; surrounds cervix to form:
    • Anterior fornix
    • Posterior fornix (deepest)
    • Right and left lateral fornices
Vaginal Examination
  • Significance:
    • Allows for bimanual examination (one hand on abdomen, one in vagina) to assess uterus.
    • Posterior fornix gives access to rectouterine pouch for culdocentesis (to aspirate fluid/pus).

External Genitals (Vulva)

  • External structures include:
    • Clitoris
    • Labia majora and minora
    • Bartholin’s glands
  • Innervation:
    • Supplied by the pudendal nerve (S2-S4), related to ischial spine.
Components of the Vulva

  • Labia Majora:

    • Longitudinal folds running from mons pubis to perineum; covered with hair and sebaceous glands; can atrophy post-menopause.

  • Labia Minora:

    • Hairless; contains erectile tissue; sensitive and tightens during intercourse; often site for female genital mutilation (FGM) in some cultures.
Vestibule of the Vagina
  • Space or cleft between labia minora; contains openings for urethra, vagina, and Bartholin's glands; partially covered by hymen.
Clitoris
  • Homologous to penis; consists of erectile tissue; becomes engorged with blood; not perforated by urethra.
    • Structure Includes:
    • Root (two crura)
    • Body (two corpora cavernosa)
    • Glans (highly sensitive tip)
    • Blood supply from deep and dorsal arteries of clitoris; innervation by dorsal nerve. FGM often involves partial or total removal of the clitoris, leading to serious complications.
Hymen
  • Thin mucous membrane partially closing vaginal orifice; crescent-shaped; allows menstrual flow to pass through.
Bartholin Gland
  • Two mucus-secreting glands located posterolateral to the vaginal orifice within the superficial perineal pouch; ducts open into vestibule near posterior labia minora.

Breast Anatomy

  • Structure:
    • Accessory glands of skin that secrete milk; overlies 2nd-6th rib, made of 15-20 lobules separated by fibrous septa (Cooper's ligaments); each lobule drains via lactiferous duct onto nipple surrounded by pigmented areola.
Location and Extensions
  • Upper lateral quadrant has an extension known as axillary tail of Spence; pierces deep pectoral fascia (foramen of Langer); communicates with anterior axillary lymph nodes.
Nipple Structure
  • Conical projection below center of breast (4th intercostal space, 10 cm from midline) pierced by 15-20 lactiferous ducts; contains smooth muscle fibers that allow stiffness or flattening; includes modified sweat and sebaceous glands.
Lymphatic Drainage of Breast
  • Specialized lymphatic channels collect under nipple and areola and form Sappey's plexus; lymph nodes include:
    • 75% drains to axillary nodes
    • 20% drains to internal mammary nodes
    • 5% drains to posterior intercostal nodes.
Levels of Lymph Nodes
  • Level I nodes: Lateral to the lateral border of pectoralis minor.
  • Level II nodes: Located posterior to pectoralis minor.
  • Level III nodes: Medial to pectoralis minor, including subclavicular nodes.